The blades of a compressor stage comprise roots engaged in axial channels of the periphery of a rotor disk and held by an annular flange formed of several sectors that is mounted via an external annular rim in an internal annular groove of the downstream face of the disk. This flange presses axially at its radially external end on the downstream ends of the blade roots, and at its radially internal end on the downstream face of the disk by means of an annular sealing snap-ring.
The internal annular rim of the groove of the disk and the annular rim of the flange are scalloped or crenellated in a matching manner, which makes it possible to bring the flange inside the annular groove of the disk by axial translation when the solid portions of the scalloped rim of the flange are in line with the hollow portions of the scalloped rim of the annular groove. The flange is then axially locked by rotation in the annular groove of the disk until the solid portions of the scalloped rim of the flange are in line with the solid portions of the scalloped rim of the annular groove of the disk and are axially pressing on the latter.
The blades comprise stops that are formed on downstream faces of their roots and that are designed to be engaged with a slight circumferential clearance between adjacent solid portions of the annular rim of the flange in order to stop the flange rotating in the annular groove of the disk. Each stop has an elongated shape in the circumferential direction and extends from one lateral edge to the other of the downstream face of the blade root, the lateral ends of the stop interacting by abutment with the adjacent solid portions of the scalloped rim of the flange in order to stop it rotating. This stop is formed by a large volume of material which significantly adds weight to the blade and hence the rotor disk.